A Voltage Controlled Oscillator (VCO) is an oscillator whose oscillation frequency is controlled by an applied input voltage. The more accurate the applied input voltage input, the more accurate the oscillation frequency.
VCO oscillation frequencies are used in radar systems, such as Advanced Driver Assistance Systems (ADAS), to generate high frequency modulation pulses. The accuracy of the oscillation frequencies from the VCO impacts the radar system accuracy.
The VCO's analog input voltage may have decreased accuracy due to low resolution, ageing, and/or temperature variations. Further, an increase in switching activity for control of the applied input voltage leads to an increase in radar system noise.
A more accurate control of the VCO is desired, but without additional cost or system noise.